The European satellite navigation system Galileo is preparing for another important step: on Wednesday, December 17, 2025, at 06:01 Central European Time, the launch of two new satellites on an Ariane 6 rocket is planned from the European spaceport in French Guiana. This is the 14th operational launch for the Galileo program and the first flight of this system on the new European heavy rocket, whereby the satellites designated as SAT 33 and SAT 34 will additionally strengthen the already existing constellation in Medium Earth Orbit.

The satellites will be placed at an altitude of about 23,222 kilometers above the Earth's surface, where they will join a constellation of more than thirty Galileo satellites distributed in three orbital planes. Their key role is to increase signal robustness and availability, ensuring that Galileo can continue to provide uninterrupted positioning, navigation, and timing synchronization services to users worldwide, 24 hours a day, seven days a week.

For the European space industry, this launch has a double symbolism. On one hand, it confirms that Ariane 6 is ready to take on the role of the main European rocket for heavy payloads, and on the other hand, it shows that the Union and its partners can maintain and develop a strategic GNSS system independent of the American GPS, Russian GLONASS, and Chinese BeiDou with their own resources.

How to watch the launch live broadcast

The launch of Galileo on Ariane 6 will be available via live broadcast for viewers around the world. The European Space Agency (ESA) is preparing a special show with connections from control centers, short reports on satellite preparation, and explanations from experts on what exactly we are watching during each phase of the flight.

The official broadcast can be followed via the platform ESA WebTV, which offers a high-resolution stream with simultaneous commentary in English. For a wider audience, it will also be broadcast on the official ESA YouTube channel, where it is possible to turn on automatic captions and follow the viewer discussion in the chat. Thanks to this, the launch from French Guiana will be accessible on almost every smartphone, tablet, or computer.

According to the announced schedule, the broadcast begins at 05:35 Central European Time, so a little less than half an hour before liftoff. In that introductory part, viewers will see the final checks of the rocket on the launch pad, short animations explaining the concept of the Galileo system, and statements from representatives of the European Commission, ESA, and the EUSPA agency in charge of the system's operational services.

Ariane 6 flight schedule for the Galileo L14 mission

The very flight profile of Ariane 6 during the Galileo L14 mission is carefully planned to safely and precisely place the two spacecraft into the target orbit. All listed time data refer to Central European Time (CET):

• 05:35 – start of the official television broadcast and introductory program


• 06:01 – liftoff of the Ariane 6 rocket from the launch pad in Kourou


• 06:04 – separation of auxiliary boosters which provide the bulk of the thrust immediately after liftoff


• 06:06 – separation of the protective aerodynamic fairing after exiting the densest layers of the atmosphere


• 06:09 – shutdown and separation of the main rocket stage


• 06:10 – 06:21 – first ignition of the Vinci engine on the upper stage of Ariane 6 and entry into transfer orbit


• 09:40 – 09:42 – second, shorter ignition of the Vinci engine for fine-tuning the orbit before satellite separation


• 09:57 – separation of satellites SAT 33 and SAT 34 above Earth


• 10:40 – 10:50 – confirmation of satellite status and official announcement of successful launch

After the completion of this nominal flight sequence, it is determined that the upper stage of the rocket is moved to a so-called "graveyard orbit", a stable path at a higher altitude than the operational orbits of navigation satellites. In this way, the risk of collision with satellites providing services is minimized and the amount of space debris in densely populated orbital layers is reduced.

Directly after the end of the broadcast from Kourou, a special event is also planned in Brussels, organized by the European Commission. There, the course of the mission will be analyzed, the first technical data on the performance of the rocket and satellites explained, and the political and industrial importance of this launch for European autonomy in space emphasized.

Why satellites SAT 33 and SAT 34 are important for Galileo

SAT 33 and SAT 34 belong to the first generation of Galileo satellites. Although often referred to as "new satellites", their main role is not system expansion, but strengthening its resilience. The constellation is conceived in the basic configuration with 24 active satellites and additional spares that can be activated if technical problems, planned maintenance, or the end of the lifespan of individual spacecraft occur.

As some satellites from earlier series have already completed their planned mission after more than a decade in orbit, the new pair of satellites ensures that users do not feel a deterioration in service quality. by adding additional spare satellites to the constellation, Galileo maintains very dense sky coverage. In practice, this means that in most parts of the world, enough Galileo satellites will be visible at any moment for precise positioning, even in conditions of tall buildings, mountainous terrain, or bad weather.

Another important task of these satellites is raising the overall robustness of the system in the context of security. Galileo, especially in combination with other GNSS systems, is becoming key infrastructure for critical sectors like energy, telecommunications, financial transactions, air and maritime transport, and public safety. Additional satellites reduce the probability that a failure of one spacecraft or signal blockage in a certain area causes wider disruptions.

Galileo – the most precise satellite navigation system in the world

Galileo is described in European documents as a strategic program of the Union, and in technical analyses, it is often emphasized that it is currently the most precise global navigation satellite system. Since the introduction of the open service in 2016, Galileo has gradually become a standard component of smartphones, vehicles, and professional equipment. It is estimated that more than five billion smartphones worldwide support Galileo, and all smartphones sold in the EU single market must be compatible with its signals.

For the average user, this means faster position acquisition and a more stable signal in urban canyons, where satellite signals often bounce off facades. In combination with GPS and other systems, Galileo contributes to navigation applications showing more accurately which lane you are in, which street you need to turn into, and measuring distance more precisely for sports and recreation.

In industry and the public sector, Galileo plays an even more important role. In rail transport, it helps the development of train monitoring systems based on satellite positioning, in maritime transport it increases navigation safety, and in agriculture, it enables the precise application of fertilizers and pesticides while reducing costs and environmental impact. Financial institutions use Galileo for precise time synchronization, crucial for high-frequency trading, and the search and rescue system integrated into Galileo enables faster location of activated distress beacons in emergency situations.

It is also important that Galileo is gradually introducing advanced services such as high-precision signal correction and cryptographic authentication, which will in the future make signal spoofing even more difficult and increase the safety of autonomous vehicles, drones, and critical infrastructure.

From first signal to full operational service: what follows after launch

Upon arrival in the target orbit, the mission of satellites SAT 33 and SAT 34 is just beginning. After separation from the rocket, the spacecraft enter the Early Orbit Phase (EOP), led by the EU Agency for the Space Programme EUSPA in cooperation with ESA and industrial partners. In this phase, expert teams monitor the operation of the satellites from control centers in Europe, checking all key subsystems – from power supply and thermal regulation to communication antennas and the propulsion system.

The first step is establishing a stable connection with the satellite and verifying that the solar panels have opened correctly and that the satellite is receiving enough energy. Then follows the orientation adjustment and, if necessary, fine-tuning of the orbit so that the satellite accurately occupies the planned orbital slot in one of the three Galileo planes. In parallel, temperature, radiation levels, and the operation of safety systems are monitored.

When it is confirmed that basic functions are stable, the phase of testing the user part of the payload begins – navigation antennas and highly precise atomic clocks which are the heart of GNSS satellites. In the following three to four months, the frequency stability of the clocks, the accuracy of emitted signals, compatibility with the existing constellation, and quality reception on the network of reference stations on the ground are checked.

Only after the completion of these detailed checks are the satellites officially included in the operational service. Then EUSPA updates the constellation data and announces that SAT 33 and SAT 34 are ready to contribute to the positioning, navigation, and timing synchronization of users worldwide. For end users, that moment passes almost noticeably, but in the background, it means another layer of safety net above our planet.

Division of roles: European Commission, ESA, and EUSPA

Galileo is a typical example of a complex European project involving political institutions, space agencies, and industrial partners. The European Commission manages and funds the program on behalf of the European Union as one of the key components of the wider EU space portfolio. The Commission defines strategic goals, adopts regulations, and ensures that the system is in line with Union policies, including security and defense aspects.

The European Space Agency (ESA) is in charge of the technical aspect: design and development of the space and ground segment, procurement of satellites and rockets, integration, and qualification tests. In the case of the Galileo L14 mission, ESA coordinates preparations with ArianeGroup and Arianespace as the main industrial partners for the Ariane 6 rocket and with satellite manufacturer OHB.

EUSPA, the EU Agency for the Space Programme based in Prague, acts as an operational and market "bridge" to users. It manages Galileo services, monitors market needs, works with industry on the development of new applications, and maintains contact with users through service centers. In the early orbital operations phase, EUSPA assumes responsibility for operational monitoring of satellites, but also for informing the public and professional users about the system status.

Ariane 6 – the new backbone of European access to space

Ariane 6 is conceived as the successor to the Ariane 5 rocket and the foundation of future European autonomy in launching payloads into space. It is a modular heavy rocket that can fly in a configuration with two (A62) or four (A64) auxiliary boosters, depending on the mass and goal of the mission. For the Galileo L14 mission, the configuration with two P120C boosters was chosen, which provides enough thrust to lift the rocket and payload into medium orbit.

The main stage of Ariane 6 is powered by the cryogenic Vulcain 2.1 engine, which uses liquid oxygen and liquid hydrogen as propellant. The P120C auxiliary boosters are full of solid rocket fuel and in the first few minutes of flight provide the majority of the thrust needed to overcome Earth's gravity. After they fulfill their role, they separate and fall into the Atlantic Ocean, while the main stage continues to climb until the moment of separation.

The upper stage is equipped with the Vinci engine, also cryogenic and, crucially, re-ignitable. precisely the possibility of re-igniting the engine allows for the precise placement of satellites into the target orbit, as well as later maneuvers by which the upper stage is taken to a safe graveyard orbit. During the Galileo L14 mission, two ignitions of the Vinci engine are planned – the first immediately after the separation of the main stage, and the second after a multi-hour ballistic flight.

Ariane 6 successfully completed its first, inaugural launch in July 2024, confirming the capability of the new system. The launch with Galileo represents the fifth mission of this rocket and the first in which Ariane 6 carries satellites of key European infrastructure. This additionally solidifies the role of Ariane 6 as the main carrier for future Union missions, including not only navigation satellites but also meteorological, communication, and scientific missions.

What users will feel after this launch

For most users of satellite navigation, the launch of two new satellites will pass without dramatic changes in the daily use of applications. Navigation in the car, ride-sharing apps, sports watches, and drones will continue to work as before. However, at the level of reliability and system resilience, the effect will be very visible – especially in the long run.

The addition of SAT 33 and SAT 34 means that Galileo will have an additional reserve in case of failure or planned shutdown of older satellites. In situations where part of the constellation is temporarily turned off due to maintenance or technical problems, new satellites will help keep the number of visible signal sources above the minimum threshold required for precise and stable service. This is particularly important in critical applications, such as air traffic surveillance, railway systems, or emergency service coordination.

Additional satellites will also contribute to better constellation geometry, which can reduce positioning errors in certain areas of the world. In combination with other improvements, such as advanced correction services and signal authentication, users will benefit in the long term in the form of greater stability, precision, and resilience of navigation solutions.

Simultaneously, the second generation of Galileo satellites is being prepared, which will gradually supplement and replace the first generation. Those satellites will bring more digital payloads, additional atomic clocks, improved antennas, and the possibility of direct communication between satellites. The mission with Ariane 6 and satellites SAT 33 and SAT 34 is a kind of transition point – the first generation is maintained and strengthened, while space is slowly being opened for the entry of the second.

How to follow the further development of the Galileo program

After the Galileo L14 mission, four more first-generation satellites remain to be placed into orbit. They will also, according to plans, be launched by Ariane 6 rockets, thereby closing the chapter of the development of the initial constellation and opening a new phase of introducing the second generation. The European Commission and ESA emphasize that the goal is to ensure the long-term sustainability of the system at least until the middle of the 21st century, alongside constant technological improvements.

Everyone who wants to follow the status of the constellation in more detail can get informed via the pages of the European GNSS Service Centre, where the status of each individual satellite is published, as well as planned maintenance works. For the wider public and development engineers, the portal UseGalileo.eu is also useful, showing a list of devices that support Galileo, as well as examples of system application in different sectors.

As for the mission itself, ESA and partners will publish updates during the early orbital operations – from the first satellite signal, through the successful opening of solar panels, to the completion of navigation signal testing. Although most users will not follow these technical notes daily, they clearly show how complex the job of building and maintaining a global navigation system is, which today seems like a self-evident part of our digital everyday life.